Deep enteroscopy with a conventional colonoscope: initial multicenter study by using a through-the-scope balloon catheter system

Background and Aims: The advent of capsule endoscopy has revolutionized evaluation of the small bowel. Capsule endoscopy has become the criterion standard as the initial examination to diagnose small-bowel abnormalities, but does not allow for tissue sampling or therapeutic intervention. Deep enteroscopy can be performed by using a balloon-assisted device or a spiral overtube for both diagnostic and therapeutic interventions of the small bowel. Deep enteroscopy is time-consuming and requires special endoscopes and accessories to perform the examination. We studied a novel through-the-scope balloon catheter system used for deep enteroscopy that uses a conventional colonoscope and standard accessories. Methods: We performed a 9-center, retrospective study using a novel TTS balloon system for small-bowel evaluation. The new through-the-scope device is an on-demand balloon catheter that is inserted through the instrument channel of a standard colonoscope and enables deep advancement into the small bowel in either the anterograde or retrograde approach. It consists of a balloon inflation/deflation system and a single-use balloon catheter designed for anchoring in the small bowel. The balloon is inflated to an anchoring pressure in the small intestine, and a repetitive push-pull technique is performed, with the endoscope sliding over the guiding catheter to the inflated balloon. The catheter may be removed and reinserted to allow for therapeutic intervention while maintaining the endoscope position. Results: A total of 98 patients were included; 52% were male, and the mean age was 55 years old (range 15-94 years). Indications included abdominal pain, iron-deficiency anemia, occult GI bleeding, diarrhea, abnormal capsule endoscopy, weight loss, protein losing enteropathy, retained foreign body, altered anatomy ERCP, and small-bowel strictures. Anterograde enteroscopy was performed in 65 patients. The average depth of insertion was 158 cm (range 50-350 cm) from the pylorus. Retrograde enteroscopy was performed in 33 cases. The average depth of insertion was 89 cm (range 20-150 cm) beyond the ileocecal valve. Overall, diagnostic yield was 44%. The average advancement time for the anterograde and retrograde enteroscopy cases was 15.5 minutes. There were no procedural adverse outcomes reported in the 98 cases. Conclusions: The TTS advancing balloon is a safe and effective way to perform deep enteroscopy by using a conventional colonoscope without the need for an overtube. Procedure time is shorter than that of other forms of deep enteroscopy. Diagnostic yield and depth of insertion are on par with other forms of deep enteroscopy. This is the largest reported study using this novel technology to diagnose and treat small-bowel disease.